I am about to buy a millstone house of about 1930. Originally it had a ground floor, a floor of traditional aspect (not millstone) was added before 1977. The facade to are there a lot of cracks due to this reason and is there a greater risk?
The millstone is a siliceous and limestone rock. This type of construction material is found mainly in the Paris Basin. The cracks can actually be due to the difference of materials used when adding the floor. Check before any purchase that the cracks are not through; if this is the case, an expertise will be necessary before any purchase. If there are only superficial cracks on the plaster, treat them to ensure the watertightness of the facade. Refer to the sheet about cracks on a wall on the site.
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